linux/arch/arc/kernel, branch v5.8

ARCv2: support loop buffer (LPB) disabling

2020-06-18T20:07:24Z

On HS cores, loop buffer (LPB) is programmable in runtime and can be optionally disabled. Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta

ARCv2: boot log: detect newer/upconing HS3x/HS4x releases

2020-06-16T19:56:37Z

Signed-off-by: Vineet Gupta

ARC: entry: fix potential EFA clobber when TIF_SYSCALL_TRACE

2020-06-16T19:56:37Z

Trap handler for syscall tracing reads EFA (Exception Fault Address), in case strace wants PC of trap instruction (EFA is not part of pt_regs as of current code). However this EFA read is racy as it happens after dropping to pure kernel mode (re-enabling interrupts). A taken interrupt could context-switch, trigger a different task's trap, clobbering EFA for this execution context. Fix this by reading EFA early, before re-enabling interrupts. A slight side benefit is de-duplication of FAKE_RET_FROM_EXCPN in trap handler. The trap handler is common to both ARCompact and ARCv2 builds too. This just came out of code rework/review and no real problem was reported but is clearly a potential problem specially for strace. Cc: Signed-off-by: Vineet Gupta

mmap locking API: use coccinelle to convert mmap_sem rwsem call sites

2020-06-09T16:39:14Z

This change converts the existing mmap_sem rwsem calls to use the new mmap locking API instead. The change is generated using coccinelle with the following rule: // spatch --sp-file mmap_lock_api.cocci --in-place --include-headers --dir . @@ expression mm; @@ ( -init_rwsem +mmap_init_lock | -down_write +mmap_write_lock | -down_write_killable +mmap_write_lock_killable | -down_write_trylock +mmap_write_trylock | -up_write +mmap_write_unlock | -downgrade_write +mmap_write_downgrade | -down_read +mmap_read_lock | -down_read_killable +mmap_read_lock_killable | -down_read_trylock +mmap_read_trylock | -up_read +mmap_read_unlock ) -(&mm->mmap_sem) +(mm) Signed-off-by: Michel Lespinasse Signed-off-by: Andrew Morton Reviewed-by: Daniel Jordan Reviewed-by: Laurent Dufour Reviewed-by: Vlastimil Babka Cc: Davidlohr Bueso Cc: David Rientjes Cc: Hugh Dickins Cc: Jason Gunthorpe Cc: Jerome Glisse Cc: John Hubbard Cc: Liam Howlett Cc: Matthew Wilcox Cc: Peter Zijlstra Cc: Ying Han Link: http://lkml.kernel.org/r/20200520052908.204642-5-walken@google.com Signed-off-by: Linus Torvalds

kernel: rename show_stack_loglvl() => show_stack()

2020-06-09T16:39:13Z

Now the last users of show_stack() got converted to use an explicit log level, show_stack_loglvl() can drop it's redundant suffix and become once again well known show_stack(). Signed-off-by: Dmitry Safonov Signed-off-by: Andrew Morton Link: http://lkml.kernel.org/r/20200418201944.482088-51-dima@arista.com Signed-off-by: Linus Torvalds

arc: add show_stack_loglvl()

2020-06-09T16:39:10Z

Currently, the log-level of show_stack() depends on a platform realization. It creates situations where the headers are printed with lower log level or higher than the stacktrace (depending on a platform or user). Furthermore, it forces the logic decision from user to an architecture side. In result, some users as sysrq/kdb/etc are doing tricks with temporary rising console_loglevel while printing their messages. And in result it not only may print unwanted messages from other CPUs, but also omit printing at all in the unlucky case where the printk() was deferred. Introducing log-level parameter and KERN_UNSUPPRESSED [1] seems an easier approach than introducing more printk buffers. Also, it will consolidate printings with headers. Introduce show_stack_loglvl(), that eventually will substitute show_stack(). As a good side-effect header "Stack Trace:" is now printed with the same log level as the rest of backtrace. [1]: https://lore.kernel.org/lkml/20190528002412.1625-1-dima@arista.com/T/#u Signed-off-by: Dmitry Safonov Signed-off-by: Andrew Morton Cc: Vineet Gupta Link: http://lkml.kernel.org/r/20200418201944.482088-4-dima@arista.com Signed-off-by: Linus Torvalds

ARC: show_regs: avoid extra line of output

2020-05-14T22:05:00Z

Signed-off-by: Vineet Gupta

arc: remove #ifndef CONFIG_AS_CFI_SIGNAL_FRAME

2020-04-13T05:27:10Z

CONFIG_AS_CFI_SIGNAL_FRAME is never defined for ARC. Suggested-by: Nick Desaulniers Signed-off-by: Masahiro Yamada Signed-off-by: Vineet Gupta

arc: ptrace: hard-code "arc" instead of UTS_MACHINE

2020-04-13T05:27:09Z

ARC uses the UTS_MACHINE defined in the top Makefile as follows: UTS_MACHINE := $(ARCH) We know it is "arc" when we are building the kernel for ARC. Hard-code user_regset_view::name, like many other architectures do. Signed-off-by: Masahiro Yamada Signed-off-by: Vineet Gupta

ARC: Fix ICCM & DCCM runtime size checks

2020-04-12T23:17:00Z

As of today the ICCM and DCCM size checks are incorrectly using mismatched units (KiB checked against bytes). The CONFIG_ARC_DCCM_SZ and CONFIG_ARC_ICCM_SZ are in KiB, but the size calculated in runtime and stored in cpu->dccm.sz and cpu->iccm.sz is in bytes. Fix that. Reported-by: Paul Greco Signed-off-by: Eugeniy Paltsev Signed-off-by: Vineet Gupta